The present invention relates to a testing device for testing the tightness of containers, and to a respective testing method for testing tightness.
In the case of packaged goods, for example in the case of pharmaceutical products, quality testing of the container in terms of the tightness thereof often has to be carried out. To this end, the possibilities of tightness testing with positive pressure or with negative pressure (vacuum) are fundamentally possible herein, and a container that has been filled and closed at normal pressure is subjected to a vacuum in a closed chamber, for example. A certain waiting time is then observed, and a change in pressure per unit of time in the vacuum range is measured. It is a characteristic of a tight container when the vacuum pressure remains constant. However, assuming a tight chamber, when the vacuum pressure rises this is a sign of a leakage of the container because a measurable equalization of pressure between the interior of the container and the vacuum chamber is performed by way of untight points in the container, for example holes or cracks, etc. In the case of a tightness test with positive pressure, in the case of an untight container and assuming a tight chamber, a pressure drop arises in the chamber, since the pressure medium by way of a crack or the like reaches the interior of the container, an equalization of pressure thus taking place. In order for the method to be able to be carried out in an economical manner, simultaneous testing of a plurality of containers in one chamber is disclosed in DE 3925494 A1, for example. However, the problem arises herein that to date, when one of the containers is untight, all of the containers have been considered untight and all containers are disposed of. However, this is often a waste of resources since the other containers would actually be usable when only one of the containers is untight.